Dataset Information

Infrared Spectroscopy of Polybenzimidazole in the Dry and Hydrate Forms: A Combined Experimental and Computational Study.

ABSTRACT: In the present article, the infrared spectrum of polybenzimidazole (PBI) in the dry and hydrate forms has been studied both experimentally and theoretically to improve the interpretation of its complex features, especially in the ?(NH)/?(OH) range, which is extensively affected by sorbed water and temperature. Time-resolved Fourier-transform infrared spectroscopy measurements were performed to monitor H2O sorption, whereas the temperature behavior was investigated by in situ measurements in the 100-450 °C range. Density functional theory calculations on simplified models of dry and hydrated PBI showed good agreement with experimental results and allowed a reliable interpretation of the observed effects. The combined experimental/computational analysis provided relevant structural information which suggested the possibility of modifying the diffusion properties of PBI and motivated further experimental activities.

SUBMITTER: Musto P

PROVIDER: S-EPMC6645080 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Infrared Spectroscopy of Polybenzimidazole in the Dry and Hydrate Forms: A Combined Experimental and Computational Study.

Musto Pellegrino P La Manna Pietro P Moon Joshua D JD Galizia Michele M Freeman Benny D BD

ACS omega 20180921 9

In the present article, the infrared spectrum of polybenzimidazole (PBI) in the dry and hydrate forms has been studied both experimentally and theoretically to improve the interpretation of its complex features, especially in the ν(NH)/ν(OH) range, which is extensively affected by sorbed water and temperature. <i>Time-resolved</i> Fourier-transform infrared spectroscopy measurements were performed to monitor H<sub>2</sub>O sorption, whereas the temperature behavior was investigated by in situ me ...[more]

PMID: 31459258

Similar Datasets

Project description:Cerebral perfusion may be altered in sepsis patients. However, there are conflicting findings on cerebral autoregulation (CA) in healthy participants undergoing the experimental endotoxemia protocol, a proxy for systemic inflammation in sepsis. In the current study, a newly developed near-infrared spectroscopy (NIRS)-based CA index is investigated in an endotoxemia study population, together with an index of focal cerebral oxygenation. Methods: Continuous-wave NIRS data were obtained from 11 healthy participants receiving a continuous infusion of bacterial endotoxin for 3 h (ClinicalTrials.gov NCT02922673) under extensive physiological monitoring. Oxygenated-deoxygenated hemoglobin phase differences in the (very)low frequency (VLF/LF) bands and the Tissue Saturation Index (TSI) were calculated at baseline, during systemic inflammation, and at the end of the experiment 7 h after the initiation of endotoxin administration. Results: The median (inter-quartile range) LF phase difference was 16.2° (3.0-52.6°) at baseline and decreased to 3.9° (2.0-8.8°) at systemic inflammation (p = 0.03). The LF phase difference increased from systemic inflammation to 27.6° (12.7-67.5°) at the end of the experiment (p = 0.005). No significant changes in VLF phase difference were observed. The TSI (mean ± SD) increased from 63.7 ± 3.4% at baseline to 66.5 ± 2.8% during systemic inflammation (p = 0.03) and remained higher at the end of the experiment (67.1 ± 4.2%, p = 0.04). Further analysis did not reveal a major influence of changes in several covariates such as blood pressure, heart rate, PaCO2, and temperature, although some degree of interaction could not be excluded. Discussion: A reversible decrease in NIRS-derived cerebral autoregulation phase difference was seen after endotoxin infusion, with a small, sustained increase in TSI. These findings suggest that endotoxin administration in healthy participants reversibly impairs CA, accompanied by sustained microvascular vasodilation.

Dataset Information

Infrared Spectroscopy of Polybenzimidazole in the Dry and Hydrate Forms: A Combined Experimental and Computational Study.

Publications

Infrared Spectroscopy of Polybenzimidazole in the Dry and Hydrate Forms: A Combined Experimental and Computational Study.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets